A power system is known which includes an electrical motor for driving a left wheel and a right wheel of a vehicle, a transmission that is disposed on a power transmission path between the electrical motor and the left and right wheels, and a housing accommodating the electrical motor and the transmission. This type of power system is provided in an electrical motor vehicle such as a hybrid vehicle or an electrical vehicle, as a front wheel drive system or a rear wheel drive system, and the housing of the power system is generally supported by a frame member of the electrical motor vehicle via mount arms (for example, see JP-A-2008-81010 and JP-A-2013-112181).
In this type of power system, however, when the distance between a torque reaction acting position of the housing and a mount arm attaching position is great, a large moment is generated at the mount arm attaching position, and thus there is a possibility that a stable support becomes difficult. Therefore, in the power system according to the related art, the above problem is solved by increasing rigidity of the housing, but when the rigidity of the housing is increased, the weight and manufacturing costs of the power system increase, and thus there is room for improvement.